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[attachment=1166]I've attached a sample of my pie chart. Does this chart depict the actual events or what they would have been without CPAP? If it shows OA events, then are those the ones that the CPAP machine didn't catch? BTW, the AHI for this session was 3.62. I'm assuming the CA part means there were no apneas or hypopneas during the session.

Sleepyhead reports the actual events as scored by your machine. So from your pie chart just over 50% of your events were central or "clear airway" (CA), about 20% were obstructive (OA) and the rest were hypopneas. These are real events which your machine didn't catch.

You need a bilevel ASV type machine to treat central apneas. However, in a lot of cases the centrals are caused by your body adjusting to CPAP, and they go away in time. As your AHI is low, I wouldn't worry too much about them at this time.

INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.

Take a good look at the detailed data and zoom in on the apneas and hypopneas. Look for patterns of where your pressure is during these events. If you notice that most of the events occur when the machine is at low pressure, you might want to add pressure. If the CA events are occurring during periods of high pressure that can be important to know too. If you can post a more complete chart showing the event flags, machine pressure and other data, it might help better interpret what is going on.

I notice you have EPR on 3 cmH2O and your average pressure during the CA events is down at the bottom of that range. Generally, central events are alleviated by dropping pressure like this on a bi-level machine but in your case, you're having pauses in your breathing at low pressure and the machine is detecting a clear airway. If it was me, I'd try to increase pressure 1 or 2 cm or possibly turn down the EPA to 1 and see if that improves things. It may make it better or worse, but I think it's worth trying some small changes and seeing if that resolves things.

The CA events do not correlate with the large leak flags you're posting but there is some pretty significant leaking going on through the night that you need to get after.

Jim, after sleeping on this, I think some experimentation is a good idea to let you visualize your response to alternative therapy pressures, but central apneas are a more complex issue that might warrant the involvement of your doctor. A simple CPAP is not the ideal device for the treatment of centrals, and you may need BiPAP ASV which is an assured volume device and actually overcomes centrals.

Keep an open mind to first eliminating the leaks, and trying to address the centrals through alternative EPR and pressure approaches, but this data could be an indication you have failed CPAP and and need a higher level machine.

With regard to the leaks, it would be helpful to know if you sense mask leaks, or if you notice dry mouth, possibly from opening your mouth at night and losing seal.

(12-23-2014, 11:41 PM)Jim Bronson Wrote: The machine pressure is constant at 9. Here's a screenshot. The AHI is flat at about 2 during the time. I'm trying to make some sense out of all this.

Hi Jim,

Slowly adapting to the therapy, lowering the pressure, and lowering EPR are the three things which commonly lower the number of Central Apnea events we get.

When we get titrated they usually want us on our back, because that is usually the worst case position, needing the highest pressure. They want the pressure high enough to handle the worst case.

If you stay off your back you and your doctor may be able to lower your pressure without significantly increasing the number of obstructive events. But your present pressure setting looks to me like it is working about right in eliminating nearly but not all obstructive events. If it were eliminating all obstructive events it would be higher than necessary, in my view, especially considering that lower pressure would likely lower the number of CA events.

I think you've been using your machine for about a couple months already, so the frequency of Central Apneas might not drop very much further from you becoming more accustomed to CPAP therapy, but neither is your present number of CAs considered excessive. In general, insurance does not cover an ASV machine unless the number of central apneas is at least 5 per hr. So your insurance (and your doctor) are probably not going to be concerned about lowering your AHI further. They may simply declare success and say keep up the good work.

Many have found that lowering or turning off EPR lowers the number of CAs they get. So I suggest you should try lowering your EPR to 2 for a couple weeks, to see if your sleep quality improves with a slightly lower EPR. If that doesn't help, you can consider lowering EPR further, or, instead, your doctor can consider lowering the set Pressure to 8.

Take care,
--- Vaughn

ADDED:
PaytonA is right. First thing to do is to reduce the amount of leaking.
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Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment. The Advisory Member group provides advice and suggestions to Apnea Board administrators and staff on matters concerning Apnea Board operation and administrative policies - not on matters concerning treatment for Sleep Apnea. I think it is now too late to change the name of the group but I think Voting Member group would perhaps have been a more descriptive name for the group.

Getting the leaks under control is important. With leaks too high the machine has trouble identifying events, and if leaks are high enough the machine will not be able to supply the therapy that is called for. My guess is that you are mouth breathing/leaking.

The secret to getting rid of mouth leaks is not something everyone can keep up during their sleep. It involves moving the tongue up to the roof of your mouth and back towards the back of your mouth. This can form an effective seal. I can maintain that kind of seal while I am awake but when I go to sleep all bets are off. A chin strap can help maintaining this seal for some people. Everyone's last resort is a full face mask. That is where I am.

(12-23-2014, 09:54 PM)Jim Bronson Wrote: I've attached a sample of my pie chart. Does this chart depict the actual events or what they would have been without CPAP? If it shows OA events, then are those the ones that the CPAP machine didn't catch? BTW, the AHI for this session was 3.62. I'm assuming the CA part means there were no apneas or hypopneas during the session.

Sorry about the newbie question.

SleepyHead shows the apneas you have while you're using CPAP. Without CPAP, your AHI would probably be a LOT higher. Even a severe apneac may have a very low AHI shown on SleepyHead.

When you're considering how bad your apnea is, especially central apnea, look and see how long the apnea is. A 60 second apnea is a lot more worrisome than an 11 second apnea. AHI just counts them, it doesn't take duration into consideration.

Also, don't panic about centrals. They aren't necessarily more harmful, just harder to elimnate.

Get the free SleepyHead software here. Useful links.
Click here for information on the main alternative to CPAP.
If it's midnight and a DME tells you it's dark outside, go and check it yourself.

Useful Links

INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.